Nattawut Uamkruea, blogger and audio gear maker who passionate in vacuum tube, audio & music.
Producing electronics projects since high school. Seriously upgrade and modify vintage audio equipment for “Real Sound” concept.
He is a co-founder of Soundaries and Sentimental Studio, all audio solution provider.
Experienced and lively explore the listening rooms & audio shops in Japan as his most favorite to do.

Sunday, May 4, 2014

Winding Resistance Step Attenuator

After searching many information of vintage step attenuator 
for use in my tube preamplifier.
I've found attenuator in the box that use Tech Lab 600 Ohm attenuators.
Tech Lab Inc. was made high quality attenuator like Daven did,
that use in audio and measurement products like Western Electric, Tektronix, etc.
Stereo Sound Japan was provide information of 
Tech Lab PK-322 that has 2 types of resistor inside.

Type I : Mold Resistor & Winding Resistance Type

Type II : All Winding Resistance Type

Attenuator in the box from Stereo Sound Japan 
was use in many test system of Tube Kingdom magazine.

Like Stereo Sound Japan Website recommended.
Type I attenuator matched with all popular and modern music and 
Type II attenuator matched with old school music like Blues, Jazz and Classical. 

Both types improve dynamic and detail of sound system a lot. 

Let's try !!!


  1. Hello NA - That's very cool, especially the nice box. Attenuators remind me of Daven attenuators. Cheers, Owen

  2. You have only used two in your pictures! Did you ever do anything with the other two? I need these for an old limiter I own! Please sell them to me!

    1. Hello,

      I bought a pair for $250 and can sell to you the same price.

      Let me know if you still interest.